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Articles you may be interested inReactions of liquid and solid aluminum clusters with N2: The role of structure and phase in Al114 +, Al115 +, and Al117 + Thermodynamic aspects of dehydrogenation reactions on noble metal surfaces Erratum: "Theoretical predictions of properties of group-2 elements including element 120 and their adsorption on noble metal surfaces" [J.Theoretical predictions of properties of group-2 elements including element 120 and their adsorption on noble metal surfaces Surface reactions of atomic and molecular nitrogen (N 2 ) with liquid group III metals: Al, Ga, and In has been investigated by quantum mechanical calculations in density functional theory ͑DFT͒ formulation, using cluster representation of metal surface. It has been shown that the N 2 molecule dissociates during adsorption on the surfaces of liquid group III metals. The N 2 dissociation energy barriers are equal to 3.0 eV, 3.4 eV, and 3.6 eV for Al, Ga, and In, respectively. They are much smaller that the dissociation energy of free N 2 molecule, equal to 9.76 eV. It has been also determined that the adsorption of N 2 on surface of liquid Al is an exothermic and on Ga and In is an endothermic process. These results are consistent with experimentally observed combustion of liquid Al in high pressure of nitrogen and the absence of combustion of both Ga and In. The process of dissolution of N atoms adsorbed on liquid Al surface has been also analyzed. The energy barriers for the direct jump of the N adatom from the surface position into the liquid Al interior is equal to 1.3 eV. This suggests that the dissolution of N in liquid Al proceeds not by direct jumps of N adatoms into the liquid interior but by Brownian motion of clusters consisting of these adatoms and neighboring Al atoms. The results of the calculations indicate that nitrogen solution in liquid group III metals consists of single N atoms strongly attached to the surrounding Me atoms.

Results of the first ab initio simulations of InN/GaN multiquantum well (MQW) system are presented. The DFT results confirm the presence of the polarization charge at InN/GaN interfaces, i.e. at polar InN/GaN heterostructures. These results show the potential jumps which is related to the presence of dipole layer at these interfaces. An electrostatic polarization analysis shows that the energy minimum condition can be used to obtain the field in InN/GaN system, employing standard polarization parameters. DFT results are in good agreement with polarization data confirming the existence of electric field leading to separation of electron and holes in QWs and emergence of Quantum Confined Stark Effect (QCSE).